I am in love with this product, I have bought three of these units (for other family members and myself) so prepare for a glowing review.I have developed a plethora of health issues over the last many years, one of them being troubling pollen allergies. I have leaky gut so the pollen slips right through those tiny tears in my gut and into my bloodstream, leaving me lethargic, swollen, and unable to eat without serious bloating. I am also extremely sensitive to pesticides, which give me similar symptoms, when the neighbors spray I'm in bed for a week! How are these problems related to this essential oil diffuser? Well, it all started when I stayed in a dusty hotel room for a week. The dust was just starting to get to me when I found a discount diffuser at a local store. I'd always wanted one and gave it a shot. Breathing in the mist from the diffuser was like breathing in pure energy. My lethargy vanished to the point where I couldn't sleep when it was going! My nose stopped running and my mood improved. These positive changes sparked some research; why did a little mist and some scented oils make me feel so refreshed?The answer was simple; Negative ions. You've probably heard of them in relation to the ocean. Ocean waves create a massive amount of these ions, which are claimed to have amazing health benefits and are documented to have calming effects. You can find negative ions not just near the ocean, but in forests, rivers, lakes, waterfalls, and when it rains. They're commonly created by the crashing (or diffusing) of water! Wow! Now here's the most important part for those of you with pollen or environmental toxin allergies like me, negative ions clear the air of dust, debris, and pollutants!!I believe the diffuser is doing more for my allergies than my expensive hepa filter!After some research I replaced the discount diffuser with this one.Pros- Best price I could find for the size- Long run time, (no more refilling water every half hour)- High output of water (I didn't just want an essential oil diffuser I wanted those lovely negative ions, so I tried to find a diffuser that could also humidify to purge any dust or crud in the air that could make me sick.)- I've had a unit for 4 months now and use it almost every day with no problems.Cons- The mist output is so high that the water can condensate on your dresser or end table. But this is solved by placing a decorative plate or towel under it (not under the unit itself, there's a fan under there)- If you turn on the light you have to cycle through 20 different light colors to turn it off again. (This is one minor annoyance I've had with the design of the unit, hardly worth mentioning but I do wish they'd made it easier to turn off the light)- Don't use tap water. (More of a helpful tip than a con, but some people might find this inconvenient, my unit developed some mold under the lid after diffusing tap water. If your water is hard, or contains mold or pollutants use filtered water in your unit, you could break it with tap water!)I will update if anything happens but so far I am enthralled with this product, if you found my review informative please let me know by marking it as helpful!